Road-finishing machine



g- 5, 1952 L. J. SAROSDY 2,605,682

ROAD-FINISHING MACHINE Filed Dec. 15, 1946 2 SHEETS-SHEET 1 v kt y gi N1 E Q w g S- INVENTOR LOUIS J.SAROSDY Aug. 5, 1952 L. J. SAROSDYROAD-FINISHING MACHINE 2 -SI-IEETSSI-IEET 2 Filed Dec. 13, 1946 4INVENTOR LOUIS J. SAROSDY 0N o N M Ma I "W ililllllli L @Nllllllllllllllllllllllllll i NN NN Patented Aug. 5, 1952 ROAD- FINISHINGMACHINE Louis J. Sarosdy, Pittsburgh, Pa., assignor to Blaw-KnoxCompany, Pittsburgh, Pa., a corporation of New Jersey ApplicationDecember 13, 1946, Serial No. 716,050

2 Claims.

This invention relates generally to machines for finishing the surfaceof a slab of concrete or other plastic material poured between spacedside forms or road rails to form a pavement such as a road.

In finishing road pavements, it is desirable under certain conditions toleave the surface thereof fiat. Under other conditions, it may bedesired to impart a transverse convexity or crown to the surface for thepurpose of drainage and the desired degree of crown may varyconsiderably. It is often desirable, furthermore, to vary the degree ofcrown while the machine progresses over the pavement, as around curves,where the desired crown increases uniformly from the apex of the curveto the point of tangency with straight roadway. Provisions haveaccordingly been made for imparting the desired curvature to the screedor other strike-off member or float of road-finishing machines knownheretofore, by elastic deformation thereof. Such members, however, havebeen quite rigid in construction because they span the full width of theroad between rails. It is necessary, therefore, to exert heavy forces onthese members in order to impart even a slight curvature thereto.

A further defect common to finishing machines having transverse screeds,floats, strikeofi members and the like, is that they do not leave theconcrete surface true and level longitudinally of the road. This hasresulted partly from the practice of supporting these members directlyon the road rails or other supports at each end, or on trucks rollingover such rails, in such a manner that irregularities in the tracksurface are transmitted bodily to the finishing member. It has thereforebeen customary to follow such machines with another having alongitudinally disposed finishing member which is oscillated back andforth across the roadtransversely as the machine moves forward, to ironout any longitudinal unevenness left by the transverse finishingmembers.

I have invented a novel surfacing member for concrete roadways capableof imparting thereto either a plane surface or a crown of desiredconvexity, without requiring it to be subjected to any abnormal stressand permitting quick and easy adjustment for various degrees of crown orconvexity. In a preferred embodiment, my invention comprises a curved,elongated member of generally bow shape disposed in a substantiallyhorizontal plane, extending across the width of the slab and mounted formovement thereover with the intermediate portion projecting for- 2wardly. The surfacing member is preferably hinged adjacent its ends to asupporting car traveling on the road rails and the intermediate portionis suspended at the elevation necessary to impart the desired shape tothe surface of the slab, i. e., either plane or crowned. The shapeimparted to the surface may be changed by merely tilting the member onits hinges; A surfacing member according to my invention may partake ofthe nature of a screed or similar strike-off member or may serve simplyto finish the surface of the slab after the concrete has previously beenspread and levelled, or it may serve both as a.

strike-off and as a finishing member. If used as a finishing member, Iprefer to provide means for vibrating the surfacing member either bodilyor locally. My surfacing member may be used alone mounted on a suitablecar, or in spaced relation with like or different members in a compositefinishing machine. With my machine, a single float only need be used,since the float is not materially affected by irregularities in thesurface over which the machine rolls such as are usually encountered inpractice.

A complete understanding of the invention may be obtained from thefollowing detailed description which refers to the accompanying drawingsillustrating the preferred embodiment. For the sake of simplicity I haveshown in the drawings a machine embodying my invention provided with onesurfacing member only. It will be understood, however, that twosurfacing members may be mounted one after the other, with an intervalbetween, one performing the function of a strike-01f only, and oneadapted for surface vibration, if that be desired. In the drawings,

Figure l is a partial plan view of a road-finishing machine embodying myinvention;

Figure 2 is a view partly in transverse section along the plane of lineIIII of Figure 1 showing parts in elevation;

Figure 3 is a side elevation such as would be seen by looking from theleft of Figure 1;

Figure 4 is a longitudinal section taken along the plane of line IV--IVof Figure 1; and

Figures 5, 6 and '7 are sections through several forms of the surfacingmember.

Referring in detail to the drawings, the illustrated example of myinvention is a road-fin ishing machine having a main frame I0 extendingbetween spaced side frames II. The side frames, as shown, include spacedchannels or other suitable structural members l2. Wheeled trucks I3 andBa are pivoted to the side frames at the forward and rear ends thereof,respectively. The wheels it of the trucks are adapted to travel alongspaced road rails 15 which constitute the side forms for a slab ofconcrete or other plastic material poured therebetween.

The main frame I!) comprises suitable transverse channels it or othersuitable structural shapes secured in any convenient manner to thesubject to undesirable vertical deflections in this travel, due to suchfactors as adjacent road rails not being precisely at the same level ata rail joint, encrustation of the forms, or, where on one or both sidesof the machine, the Wheels roll over previously cast slabs, the uppersurface of such slabs is uneven at their edges. I provide a constructionby which such local wheel deflections have but slight effect upon thegrade which the surfacing memberdefines in its travel, by the pivotalmounting of the two-wheel trucks I3 and i3a on the ends of the sideframes H, the torsional flexure of the frame i9, and the manner ofsuspending the finishing member therefrom which will ,be subsequentlydescribed in detail.

The car is driven by an internal combustion engine l9 mounted thereonthrough a transmission 26 including speed-chang and reversing gears.Cross shafts 2i extendoutwardly from both sides of the transmission 28,the outer ends being suitably journaled in bearings 22 on the sideframes I 1. Each shaft it drives a jack shaft 23 through gearing-24. Therear trucks in are pivoted to the side frames on drive shafts 25.Chain-and-sprocket drives 28 connect the shafts 23 and 25. Th wheels ofthe trucks i301 have sprockets thereon whereby they are adapted to bedriven from shafts 25 by chainand-sprocket drives 2?. If desired the carmay be pulled or pushed forward by other means. The shafts 2! may beselectively connected to the transmission 2!] by clutches 23 havingoperating levers 29; All of these features are conventional andwelldrnown in the art of road-finishing machines. A rigid, elongatedbow-shaped surfacingmember 30 extends between the side frames l l and issuspended below them and the main frame Iii. The member 33 may be of anydesired shape in section, three types being shownin Figures 5, 6 and 7.The circular section 39a, which is the section also shown in Figures 1through 4, may conveniently b formed from a length of pipe. The member38 may also be of any other desired shape in section, e. g.,fiat-bottomed as at 3% or of plate form as at 38c. Drag linksv 3! arepivoted to cross pieces 32 secured to the side frames H and the outerends of the member 39 are hinged to the rear ends of the drag links 3!onpins 33. The pins 33 pass through clevises on hanger rods 34. Thehanger rods are pivoted to bell cranks 35 mounted on shafts journaled inthe side frames I I. The hanger rods may be adjusted vertically relativeto the bell cranks by means of nuts 34a turned on'the upper ends'of therods which are threaded.

, The intermediate portions of the member 33 are suspended by links 37pivoted thereto. These links are also pivoted to cranks 38 on a crossshaft 39 journaled in bearings secured to the forward cross member 16 ofthe main fram it. The surfacing memberfm may thus be caused to tilt onits hinge pins 33 by turning the shaft 39. It will be evident that, whenthe bottom of the midportion of the member is at the same elevation asthe bottom of its ends, it Will finish the road slab to a plane fiatsurface. If th intermediate portion of the member 39 is tilted upwardlyrelative to its end portions, however, the surface of the slab will beshaped to a smooth convex curvature, the degree of convexity dependingon the elevation of the bottom of the mid-portion of the member abovethe bottom of its ends.

The suspension links 34 and 37 are disposed to hang in the frames II andIii, respectively, so that the member 36 lies with the center of gravityof its working surface substantially equidistant from the four truckpivots and 25a. The side frames ll, moreover, are preferably of a lengthbetween pivots 25 and 25a which is great as compared to the projectedlength as viewed in side elevation of Figure 3, of the surfacing member30. Vertical deflections of pins 25 or 2505 individually, due to localirregularities in track such as previously mentioned are only half thedeflection of a wheel, and this is reduced onefourth again (toone-eighth) at the center of gravity of the member 30, so as to reduceits bodily deflections due to surface irregularities to negligiblemagnitude. Furthermore, the finishing surface defined by member 36 isnot unduly warped, this warping being less the longer the end frames aremade. The suspension of member 39, therefore, provides not merely amember readily adjusted to grade and crown, but one operatingsubstantially in properly adjusted position regardless of smallirregularities, bumps and road rail joints which deflect the Wheels fromproper level.

For the purpose of turning the shaft 39 through a small angl to adjustthe mid-portion of the member to the desired height, I provide the shaftwith a crank d8. Bell cranks 6! are pivoted above the crank to onbrackets 42 secured to the main frame It]. A screw shaft 53 is journaledin a thrust bearing 44 pivoted to the forward end of the bell cranks Hand is threaded through a nut pivoted to the crank 4- 3. It will thus beapparent that, so long as the bell cranks H remain fixed, rotation ofthe shaft 43 will cause angular movement of the crank 38 to turn theshaft 39 for tilting the surfacing member 35 about its hinge pins. Tofacilitate this adjustment, the shaft 43 is provided with a hand wheel46.

The bell cranks 4| are normally held in their illustrated position by acable 47 secured to the upper ends thereof and to a drum d8 fixed on ashaft d9 journaled in the main frame E0. The shaft 49 is provided with ahand lever 5% whereby it may be turned through a small angle. The leverlimits rotation of the drum 48 in the direction for unwinding the cable47. The cable is connected to the bell cranks by an eye-bolt 5! havingadjusting nuts 52 whereby sufficient tension may be maintained in thecable to hold the bell cranks it in the desired angular position. Cables53 similarly secured to the bell cranks 35 extend around guide pulleys54 and 55 journaled on the main frame and are securod'to the drum 38. Itwill be understood that, by this construction, the surfacing member 30may be bodily lifted by pulling back on the lever 59. This raises themember entirely out of contact with th surface of the slab. Thus, afterthe car has traveled along a limited length of the pavement, the member30 may be'raised and the machine reversed for a second pass of themember over the slab if desired. When the lever 50 is again thrownforward, the surfacing member 39 descends to the position for which itwas pre- 7 viously adjusted, whether horizontal or tilted upwardly atthe intermediat or forward portion. That is to say, th bodily lifting ofthe member to permit a second pass over the slab does not interfere withthe angular adjustment of the member or necessitate any change therein.At the same time, the angle between the plan determined by the bottom ofthe surfacing member and the horizontal may easily be adjusted simply byturning the hand wheel 43.

The means mounting the member 30, i. e., the drag links 3|, hanger rods34 and links 31, have sufficient lost motion therein to permit slightbodily oscillation of the member 30 in a generally longitudinaldirection with an amplitude of, say To cause such oscillation, I mountvibrators 56 in spaced relation on the member 30. These vibrators may beof any desired type. If electrically operated, they may be energized bya generator 51 driven by the engine 19. Instead of being of the typeadapted to cause bodily longitudinal oscillation of the member 30, theymay be of the type to create merely local vibration thereof. In eithercase, passage of the surfacing member over the concrete is facilitatedby vibration or oscillation thereof;

It will be apparent from the foregoing that the invention ischaracterized by numerous advantages over road-finishing machines asknown heretofore. In the first place, the bow-shaped surfacing member,while rigid in itself, may be adjusted quickly and easily, by reason ofits construction and'mcunting on the car, to impart either a plane or acrowned surface to the roadway and may be adjusted for the proper degreeof crown, all without imparting any substantial stress to the member orits supports. In addition, the member may be raised entirely clear ofthe pavement slab to permit the machine to back up for a secondpass, ifdesirable. As has already been noted, the machine may be employed simplyto impart a finished surface to the concrete which has already beenspread and levelled or it may be used to distribute uniformly betweenthe road rails concrete which has simply been dumped therebetween'inpiles. The bow shape of the member is useful in spreading concretenormally when used in the manner of a screed.

The side frames extend forwardly and rearwardly beyond the intermediateportions and ends, respectively, of the surfacing member. This lendshorizontal stability to the surfacing member and tends to eliminateminor variations in the surface of the finished slab. The lost mo-v tionin the mountings for the surfacing member permits bodily or localoscillation thereof without imparting vibration to the frame of the car.

Although I have illustrated and described but a preferred embodiment ofthe invention, it will be understood that changes in the constructionand arrangement of parts may be made without departing from the spiritof the invention or the scope of the appended claims. The terms roadrails and side forms where used in the claims include any equivalentstructure providing a lateral wall confining the plastic mass beingfinished and having a surface over which the car can be rolled, such asthe edge of an adjacent previously cast slab, or spaced form walls andtrack structures separately and independently assembled and supported.

I claim: v

1. Slab-finishing apparatus comprising a car adapted to travel alongside forms, an elongated rigid bow-shaped member extending between saidforms and hinged adjacent its ends to said car, a shaft journaled on thecar, a crank on the shaft, a link pivoted to the crank and said member,a bell crank pivoted on the car, a second crank on the shaft, a screwshaft journaled on said'bell crank actuating said second crank to adjustsaid member, and means for lifting said member bodily, whereby said slabmay be provided with a planar or crowned contour and said member thenlifted if the direction of movement of said car is to be reversed.

2. In a machine having a car adapted to travel along a road surface ofconcrete or the like to contour the same, in combination, an elongatedbow-shaped tubular member hingedly connected to said car'so as tosubstantially extend across said surface, said member defining a planegenerally parallel to the plane of movement of said car, means forvertically adjusting the height of the ends of said member, independentmeans for vertically adjusting the height of the midportion of saidmember, and means for bodily elevating the ends and mid-portion of saidmember above said surface, whereby a plane or crowned surface may beprovided by the relative adjustment of the height of said mid-portion tothe height of said ends and the entire member elevated above saidsurface if the direction of movement of said car is reversed.

LOUIS J. SAROSDY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

